Assassin series RE: Of turtles and unstable mutagen
by Askre5
Summary: The Turtles from the 80's toon 'verse are rewarded with quite a surprise when a certain someone attacks in their world. Conclusion of a plot point from Shattered Shells.
1. Chapter 1

**A/N:** Story originally written and posted on. 18/03 2008

Welcome to Of Turtles and unstable Mutagen. This story addresses a plot point in Shattered Shells where I had 2k3-Don discover that the mutagen in the 80's Toon turtles is highly unstable.

This is based heavily on the last two seasons of the 80's Toon, where this very subject was actually explored, but those two seasons are no longer considered into the Assassin series.

It happens few weeks after The Nightmare Codes, but that story is only vaguely referred to.

And the drill is as usual, 80's Toon turtles full names, 2k3-turtles with nicknames. And AU turtles with titles.

* * *

 **Disclaimer and Legal stuff:**  
Teenage Mutant Ninja Turtles®, including Raphael®, Michelangelo®, Leonardo®, Donatello®, April O'Neil®, and Splinter® are registered trademarks of Viacom International Inc. Based on characters and comic books created by Peter A. Laird and Kevin B. Eastman.

I do not own them in other words.

This story is written purely as a homage to the Teenage Mutant Turtles and not meant for any commercial profit or infringement on copyright. This story will immediately be removed if Viacom International wishes so.

Other characters are © Hermann Gunnar Sigurðsson (Askre).

AU turtles in all their varety are based off the TMNT.

The story, is copyright © 2008 by Hermann Gunnar Sigurðsson (Askre).

 **Story rated T for slight language and violence.**

 **To fully understand this story, being familiar with the Assassin series is very important.**

 **This story is canon to the Assassin series.**

 _Sum: The Turtles from the Old toon 'verse are rewarded with quite a surprise when a certain someone attacks in their world. Conclusion of a plot point from Shattered Shells._

* * *

 **Chapter 1**

 **80's TMNT World**

It was just a regular day for New York City. It was early morning; shops were opening, as were other places. People were reporting to work all over town or doing some other errands needed for that day. It looked like this would be just another boring day for the regular citizens.

April O'Neil was as always in her yellow jumpsuit in front of a camera, operated by the Channel 6 news crew. Vernon was in the blue van handling the controls, the man snorting something about how he should be in front of the camera instead of the woman. However, he was ignored.

"This is April O'Neil, saying good morning New York." The news reporter began her morning report.

"We are here in the Midtown to do our daily morning report. Currently in front of City Bank that has just opened for the day, so people can do their regular banking," she continued with a smile.

 _Get on with it woman,_ Vernon thought with a grunt but didn't otherwise say a word. He had gotten a stern reminder that he was not to interrupt this program. In other words, Burns threatened to fire him.

"We will be going through the..." April was interrupted when suddenly a huge explosion erupted from City Bank.

The woman and the whole news grew threw themselves to the ground as rain of debris came over them. Dust cloud began covering the whole street. Coughing, April managed to rise up and helped the cameraman to stand. The van had been thrown aside and out of it Vernon came crawling and complaining.

"What on earth is happening," he whined as other crewmembers helped him to his feet.

"I don't know," April said startled and averted her eyes from the dust. She missed several figures running towards the gaping hole that was now on the bank building. _But I better call the turtles._

* * *

Inside the bank, the dust went inside as well. It created a ghostly fog effect, surrounding the startled people inside. Nobody had been hurt, as no one had been too close to the explosion.

"Ladies and gentlemen," a rough and deep voice suddenly addressed them; there was a hint of Japanese in it. Somebody was walking through the large hole on the building.

"Please assume the customary screaming and running for your life. Don't worry, we won't stop you." The speaker came now clearer into view.

It was a very dark-green turtle. A bit larger than the ones the people of New York were used to and looked more muscular. He wore a blood-red mask, camouflage pants and heavy army boots. Encircling his waist was a belt with various explosives and handguns, he had a combat knife as well and a sai. Across his plastron went a single cartridge strap and on his back the reptile carried a shotgun.

He grinned nastily at the reaction, first there was shock, then screaming and many began running. After the turtle came several figures dressed in dark gray uniforms and their heads mostly concealed by helmets. Their silhouettes suggested a turtle shape, they all carried rifles and their gloved hands only had three fingers each.

"You know the plan boys, make it look like we're robbing the place," the blood-red masked turtle chuckled and pointed towards the vault. The uniformed figures nodded and four of them began running further into the building. The others aimed their weapons at various people.

The dust cloud was finally settling enabling anybody outside to see inside. April gasped when seeing what was going on. The unknown turtle was in clear view and made no attempts to conceal himself. Then he leisurely picked up a pack of cigarettes and picked one out, lighted it and began smoking.

"What the... it's one of those damn turtles." Vernon as well spotted the reptile, but April knowing very well that this was not one of their turtles slapped him on the head.

"No you idiot, this is not one of the ninja turtles," she hissed. The woman recognized the description, having heard it from her friends and memorized it. "It's the Demolisher."

"The who?" Vernon asked confused.

"Don't ask, let's just hope the turtles are here in time," April said and glanced at her turtle-comm, it had only been a half a minute since she had contacted them.

* * *

"Sir, we have secured the perimeter," a gray clad turtle soldier reported to the Demolisher.

"Good, do as much damage as you like, we need to make sure they get our attention," the blood-red masked one said with a smirk. The cigarette dangled from the edge of his mouth. The soldier nodded and left.

"You got our attention fie..." the sudden halt of the voice, suggested that the owner had realized whom he was addressing.

The Demolisher turned and now grinned madly. At the edge of the opening stood now four turtles, all clad in different colored gear with letter buckles on their belt. They were all frozen for a moment in shock to see who it was.

"Ah, just in time," Demolisher Raphael said chuckling.

"The Demolisher, here?" Donatello whispered, he was currently the tallest and slightly more massive than his brothers. He tightened the grip on his Bo-staff.

"What are you doing here?" the R-wearing Raphael demanded, pointing at his counterpart with a sai. There was though slight nervousness in his voice, he remembered all too well his imprisonment and how the Demolisher had handled him.

Leonardo frowned heavily; he carried the most scars of his brothers, both mental and physical. He desperately hoped that the assassin wasn't around either. It was then the ninja noticed the turtle soldiers, all aiming their weapons at them.

"Guys... be careful," he whispered to his brothers. They had noticed the others as well.

"For your question, I am doing this." The Demolisher ripped up from his belt what looked like a grenade and threw it at them.

"Get to cover!" Leonardo shouted and the four turtles ducked out of the way.

It was only a very strong smoke bomb; it immediately began emitting a fog like smoke. It was much thicker than the dust debris before. The ninjas were temporarily stunned and couched violently.

"Try not to breath... too hard," Donatello instructed and rose slowly from his spot.

"Attack guys!" Leonardo ordered and the four turtles rushed into the building.

So far the fight was terribly easy; the soldiers didn't put up too much resistance. They shot at them but didn't exactly seem to aim. Leonardo already disarmed two and threw them at the nearest wall. Michelangelo used his nunchaku to knock out another one. Raphael threw one soldier across the room.

"There you are!" Donatello slammed into the Demolisher who was thrown to the ground. The purple-clad turtle then sat astride on the bigger one, pinning him down with the Bo sneering at him.

"What are you up to, why are you robbing a bank in our world?" he demanded but was surprised to see the Demolisher just smirk. Around he could hear his brother fight, but the visibility was very poor thanks to the smoke bomb.

"Poor fool, we aren't robbing a bank. We just put up a little show, to get your attention," the other turtle said and laughed. Donatello frowned in confusion but then there was a prick in leg.

"Ow! What the..." The purple clad turtle looked down and to his surprise saw a syringe in the Demolisher's right hand, it was currently jammed into his thigh.

"Say goodnight, I think you are familiar with this sedative," the blood-red masked one said with an evil grin.

"Oh no... but my body can't handle..." Donatello couldn't get any further as everything got black and he lost consciousness, falling on top of the Demolisher. The other turtle quickly pushed him off and was immediately approached by turtle soldiers wearing gas masks.

"Ok we got our target, bail out!" The camouflage-pants wearing turtle growled. The soldiers picked up the unconscious ninja and dragged him off.

The others were taken by surprised when suddenly the soldiers fought much harder. Raphael was forced to jump behind a desk when rifle blast nearly hit him. Leonardo and Michelangelo ended up cornered behind a wall. The soldiers were making sure they didn't go anywhere.

"What the heck, they weren't fighting like this a minute ago," the M-wearing turtle said confused.

"Hey the blasts stopped," Raphael called and carefully peeked from behind his hiding place. The fog was clearing and they were the only reptiles in the bank.

"Huh, correct me if I'm wrong, but weren't we fighting a bunch of the ex-Emperor's turtle soldiers plus that crazy Demolisher?" The R-clad turtle slowly rose up looking around confused.

"Wha… where... hey where is Donatello?" Leonardo realized that the purple-clad turtle hadn't given a single sound.

"I think he went straight for the Demolisher," Michelangelo said and froze when an idea hit him. "You don't think..."

"Oh crud." Raphael palmed his face when he came to the same conclusion and his brother.

"Guys!" Into the bank, April O'Neil came running.

"No time April, these bastards just abducted Donatello," Leonardo said and picked up his turtle-comm.

"But was this turtle, was it this Demolisher you told me about?" she asked, now even more worried when hearing what had happened.

"The one and only, but now the question is, why was he attacking a bank only to take off with our brother." Raphael frowned and looked Leonardo who was punching buttons on the communicator.

"Come on, there was a connection, so I got through. Oh dammit Donatello always contacted them this way," the blue-masked turtle grunted. Suddenly a voice emerged from the communicator, there was no face on the screen since the other line didn't have one.

"This is Leo," a voice said through the Turtle comm.

"Leo? You're back, how are you doing?" Leonardo asked, temporarily stunned to hear his friend. There was a soft chuckle from the other line.

"Much better thanks, Leonardo. So what's up?"

"We got trouble in our world, the Demolisher just attacked a bank but it seems to have been a setup to kidnap Donatello," the L-wearing turtle quickly explained.

"We're on our way, we'll arrive in your lair," the other voice said instantly needing no further explanation. Leonardo hung up his communicator and looked at his brothers.

"Well we are getting help, let's go," he said and rushed to the blast hole and his brothers fast on his heel. April followed as well, not intending to miss this adventure her friends had found themselves in.

* * *

Donatello groaned as he slowly came to his senses, the ninja opened his eyes but had to close them again. A very bright light shone right above him. The turtle tried to rise but found himself strapped to something. The D-wearing one tried to break free, but despite his added strength, it was no use.

"Judging from your struggles, I take it that you are awake," a familiar voice addressed him.

"You!" Donatello growled when seeing the familiar face of his ex-emperor counterpart. The olive green turtle was wearing the customary lab-coat and underneath he was wearing black clothes.

"Struggle all you want," the former overlord said smirking when the prisoner added more efforts in his attempts to break free. "I designed the drug that enhanced your strength, so I know how strong you are and what is necessary to hold you down."

"So what do you want?" The D-clad ninja snorted.

"Well, I have always wondered why your body system reacted so violently to the strength enhancer. However, I never really got a chance to test it, since you were the prisoner of the Demolisher. But now I have some spare time," ex-Emperor Donatello explained.

The purple-masked one stopped struggling. He was shocked to hear this; the turtle had no recollection about his violent mutation. All the ninja had to go on was what his brothers had told him. The only constant reminders that it had in fact happen, were his added height, strength and denser body.

"I have already collected a blood sample from you, I'm waiting for the first test results to come," the ex-emperor said with a shrug. Donatello immediately checked himself over the best he could and noticed a needle wound on his right upper arm.

"You had to have used a sharp needle, I can barely be cut with Leonardo's katanas any longer," the ninja muttered. _Wait a minute; the Demolisher used a syringe on me as well._

"You honestly think I would go through all this trouble to capture you, only to not have equipment that works?" the former overlord snorted and walked to a control panel on the room and began working on it.

Donatello grunted and began looking around; this was some sort of a lab though a bit small. There was only room for a single computer console, the table he was on and another smaller table that could be rolled around on wheels. The D-wearing turtle frowned heavily when noticing the canister on the rolling desk; it contained glowing purplish/pinkish goo.

 _Wait a minute… that's the mutagen that mutated us. Shredder and Krang's mutagen._ His eyes opened wide in surprise. The ex-Emperor must have swiped it when he, the assassin and the Demolisher ransacked the Technodrome before blowing it up.

"W-what is your plan with that mutagen over there?" the turtle asked mildly concerned. It had powerful metamorphosis properties, able to change any living being into anything it had last been in contact with. It was quite different from the mutagen that had mutated the ex-emperor and many other counterparts.

"Hm? Oh, well I have been studying it and now that I have you and know you were mutated with it, I wanted to compare few samples," his evil counterpart responded glancing his way and smirked.

"It's very unstable." Donatello pointed out, not really knowing why. The ex-emperor nodded, having discovered the very same.

"It can be stabilized though and I have actually discovered how," the former overlord told him and began working on the console again. "And you my friend are going to be the first one to try it."

"ME?" Donatello froze.

"According to the test results I'm getting, the reason my strength enhancer reacted so violently with your body, was because of the unstable mutagen in your system. Your current mutation is irreversible I'm afraid, but still it would be interesting to see if I can't stabilize the mutagen but I need a live subject for it first," ex-Emperor Donatello told him. "And why mutate a new animal, when I already have one on my table?"

 _Guess I can't argue with that._ The D-clad ninja gulped.

* * *

"And when the smoke began to clear, Donatello, the turtle soldiers and the Demolisher were gone," Leonardo finished his explanation.

"The Demolisher," Raph growled hammering his right fist into the open left hand.

"Why kidnap Donatello, that doesn't seem like his style." Don rubbed his chin thoughtfully. The non-letter wearing turtles had arrived just shortly after Leonardo had called them. The letter-buckle ninjas met with them in the living room. April raised an eyebrow when seeing her friend's four counterparts, they were bit taller, more muscular and in different skin color.

"He can't be working alone," Leo said with a frown. "He almost only does something when it's for the assassin, he is his employee. Loyal one at that."

"He did have few of the turtle soldiers of ex-emperor Donatello," R-wearing Raphael mentioned.

"Right you mentioned that… but it can't by Yuri and his gang. They must have had access to more soldiers." The olive-green turtle looked at his brothers. "You guys think the ex-emperor is involved?"

"If he is, then the assassin is most likely there too. The ex-emperor is also his employee." Leo's brow sunk even heavier.

"Should we contact the magistrate and his brothers?" Mikey asked worried.

"Not just yet. We can't keep running to them for every situation we land in involving the assassin," his basic-green brother said. "Let's try to get to the bottom of this on our own first."

"Heh, I'm all for that." Raph grinned eagerly. Don nodded and went into his duffle bag to pick up a scanning device.

"Let's see if Dontello's tracking device in his D-buckle is still in this world." The purple-masked one began working on the device.

April noticed Splinter standing in the doorway and looked very worried. However, so far the elder had said nothing, allowing his sons and their friends to work. The woman approached the brown rat, who nodded to her smiling little bit.

"I thought that since they were counterparts that they would look exactly like the guys," she commented in a whisper.

"Ah yes, we have learned strange things about other worlds ever since encountering the assassin so many years ago," Splinter told her. "But they have been good friends."

"Yes! He's still here, meaning they must have put up a temporary base within the city." Don grinned having caught a signal on the scanner.

"Well, let's go get him then," Leo declared standing up from the chair.

"Wait, I'm not too familiar with your New York, what district is this?" the olive-green turtle asked Leonardo. The L-wearing turtle glanced at the scanner and frowned a little.

"This is one of the factory districts, mostly old and abandoned factories," Leonardo told him.

"Great, last time we met the Assassin in a factory, it almost blew up on us," Mikey complained causing his M-wearing counterpart to cringe.

"And knowing that the Demolisher is there, it is probably rigged to explode." Raphael palmed his face.

"That's a risk we have to take," Leo stated firmly. "But we better approach from different directions. In case they have security up and running."

"Knowing them, they probably do," Don concurred.

"Right, Raphaels and Michelangelos, you take the turtle blimp. The rest of us take the van," Leonardo ordered and began approaching the exit, the other turtles followed without question.

April was about to follow but Splinter grabbed her arm to stop her. The old rat shook his head at the surprised woman.

"I fear April that this time I cannot in good conscience let you follow them. These enemies are far too dangerous and human lives mean nothing to them," the Ninja Master told her.

* * *

"Everything is prepped and ready if they come," the growling voice of the Demolisher emerged from the communicator.

"Good, wouldn't want them to spoil the party too soon," the ex-emperor said and looked down at his counterpart. "How is our associate?"

"Edging for a piece of them, can't blame him," the Demolisher cackled.

 _Associate?_ Donatello frowned. That couldn't be the assassin; they always referred to him as their employer or boss.

"Not that I expect you to answer, but what associate do you have here?" the D-wearing ninja asked. His counterpart raised an eye-ridge but smiled.

"I do believe you know him, at least he was familiar with you and your brothers and told us what we needed to do to get your undivided attention," the former overlord told him.

Ex-Emperor Donatello then began working on the computer console, ignoring his prisoner. The ninja slunk his head back down to the table and sighed. So far the tests hadn't exactly been gruesome. More blood had been removed from him and something had been injected, but nothing extraordinary painful had occurred.

"Hm, it seems that I was wrong about the stability… I'm going to have to run few more tests," the former overlord muttered.

 _If the guys get me, I'll have to remember to snatch that canister of mutagen. I'm sure Don and I can figure out how to stabilize the mutagen in my brothers and I,_ Donatello thought.

"Yo, we are getting company, shall I prepare our guard dog?" the Demolisher suddenly spoke through the communicator.

"Yes, that would be most appropriate, he should be a sufficient delay along with our associate," the ex-emperor answered. This caused his counterpart to frown in worry.

 **End chapter 1**


	2. Chapter 2

**A/N:** Chapter originally written and posted on. 29/03 2008

* * *

 **Chapter 2**

 **80's TMNT World**

"Whoo hoo, talking about riding in style," Mikey cheered as the Turtle Blimp soared through the sky.

"You guys not much for the concealment, are ya?" Raph glanced at his counterpart who was flying the contraption.

"Don't look at me, Donatello designed it." The R-wearing turtle shrugged. His friend just grinned; he knew very well that the letter-wearing turtles didn't have to worry as much about hiding anymore. Seemed like in this world, the people had simply gotten used to the four ninjas or just didn't care enough to do something about it.

"Ok guys we are approaching position, we'll take the roof entrance," Michelangelo said in his turtle-comm.

"We are still a bit away, wait for us to be closer before entering," Leo ordered from the other line.

"Right, they have proven that four against two isn't necessarily bad odds for them, or even four against three," Raphael grunted.

"I'm just glad it isn't that cyborg clone we are dealing with, talk about a creepy character," Mikey shuddered.

"Come on, he couldn't have survived," the R-wearing turtle said but his M-clad brother grabbed his beak.

"Shh compadre, every time you say that the bad dudes appear," Michelangelo whispered alarmed.

"Woops, sorry." Raphael grinned uneasily after his beak was released.

"Alright enough jabbering, let's get ready," Raph growled, his counterpart nodded and brought the blimp to a specific factory, clearly abandoned. Soon they saw the Turtle-Van come tearing through the streets and towards it.

"Alright guys, go in," Leo's voice came from Michelangelo's turtle-comm.

The M-wearing turtle threw down the rope and the four turtles onboard slid down it to the roof. They all drew their weapons and went straight for the entrance. Raph led, he kicked the door down before darting inside and the others followed close by.

"Knowing who are operating this, they are probably aware of us being here already," Raphael muttered as they went down the stairs.

"Right," his very-dark green counterpart agreed as they entered a room. Standing right in front of them were four Turtle Soldiers. "And here is the welcoming committee."

* * *

Leo, Don and Leonardo entered through a backdoor. They were almost already in the main factory area. They had their weapons up and carefully crept close to the wall towards the next entrance.

"Ok so it is the Demolisher and few turtle soldiers. Getting past them is probably the difficult part," Leo whispered as they approached the doorway.

"The ex-emperor is no fighter, but he can still be tricky." Don nodded, eyeing quickly around.

Leo put a hand on the doorknob, but the moment he did there was a low growl. The turtles looked at each other then around. Suddenly something jumped up and landed on a large crate. There it sat in a crouched position. A bluish-green turtle with scars all over its body, on the hands, it had clawed gauntlets and the kneepads had spikes. The eyes were bloodshot and insane.

"Make that, the Demolisher, few turtle soldiers and Mad Michelangelo," the purple-masked ninja corrected his brother.

"Nice," Leo grunted, knowing this mutant was far tougher than he looked and very vicious when battling.

"And don't forget ol' Leatherhead." A deep Cajun accented voice suddenly rumbled and the doors were kicked down. The ninjas were forced to jump away.

"Leatherhead!" L-wearing Leonardo frowned when seeing the seven-foot tall gator walk in with a large toothy grin on his long muzzle. In his hands he held a similar rifle and the ex-emperor's turtle soldiers wielded.

"Yeah it's me by gumbo. Looks like Ah finally tangled with the right turtles," the big reptile declared and roared in laughter. He then aimed the rifle. "And now Ah make jambalaya stew outta yous with mah new friend!"

"So this is your version of Leatherhead." Leo eyed his friend who nodded.

"Nice fellow," Don muttered while readying his Bo.

The gator fired from his rifle, sending laser blasts almost directly at the turtles. Mad Mike took this as a cue to charge from the other end. The ninjas were forced to jump into separate directions. Don ended up having the mad mutant chasing him.

"There be no escaping ol' Leatherhead and his friend Mad Michelangelo, Ah guarowntee," the large reptile said and kept firing at blue masked turtles who ducked behind an old assembly line.

"His aim is getting better." Leonardo was surprised they hadn't even managed to approach; the blasts came too close for comfort.

"How strong is he?" Leo wondered and risked peeking over only to quickly duck several laser blasts.

"Very strong," his counterpart answered.

"Well we can't sit here, one good thing is that he can't fire at us both at the same time, so let's split up," the basic-green turtle said, Leonardo nodded in agreement. They quickly jumped up and took off in the different directions.

"Ah blast you into tiny pieces!" Leatherhead growled and fired towards Leonardo.

"Hey!" the L-wearing turtle just managed to jump behind crates.

Leo frowned and managed to backflip closer while the gator's aim was not on him. Then quick as a lightning he hewed with his swords. The rifle went into pieces and the ninja now faced the big reptile.

"Ah'll teach yahs to destroy mah rifle," Leatherhead growled and grabbed a bullwhip from his belt.

"Not today you will," the blue-masked turtle declared and jumped aiming a kick at the gator's head. It connected but it only caused his opponent to stagger a bit backward shaking his head.

 _Ok, strong and tough, but I should have guessed._ Leo got ready and jumped out of the way when the whip came cracking.

* * *

Meanwhile Don was busy deflecting the blows from Mad Mike. The mad turtle was already on his way to destroy the Bo with the constant blows from his claws. The purple-masked ninja had already tried punches and kicks, but it barely phased the other reptile.

 _Right, I forgot he's resistant to pain._ Don managed to quickly sidestep and swung his staff. It connected hard with Mike's head.

The mad mutant snarled and grabbed for the Bo with his teeth. Then he tried to viciously shake it off from the ninja. The purple-masked turtle struggled to free his weapon from his opponent.

"Hey, let go you beast," he grunted and pulled hard. The staff went into two. _Oh shell!_

Don quickly ducked when Mad Mike spat the weapon remains out of his mouth and jumped for him. The crazy mutant flew over the turtle and landed on wooden crates, smashing them in the process. The ninja rose up and picked up a discarded long steel pipe.

"Let's see if this will work better," he muttered but then had to duck again but this time from a rifle blast.

"Oh crud, Turtle Soldiers," Leo shouted when five uniformed reptiles suddenly arrived firing from their lasers. "Guys we have to fall back."

"Right," Don agreed with his brother. Mad Mike was rising again, angrier as ever and Leonardo was now fighting Leatherhead.

The three ninjas barely managed to escape from their opponents and back the way they came. They hurried back into the turtle van and drove off under cover of laser fire. Growling Leo picked up his Shell-cell.

"Raph, we were forced to run, they got heavy back up," he called through. "We are going to try another way in."

"Raph?" The blue-masked turtle blinked when he realized that his brother had never answered. Then there was laughter on the other end, the three turtles frowned when recognizing the voice.

"Hey there Ninja Boy. Like our new, much more improved Turtle Soldiers?" the laughing voice of the Demolisher came through the cell.

"Demolisher! What have you done with them?" Leo snapped. His counterpart cast him a glance before eyeing the road again.

* * *

"Oh nothing much," the Demolisher cackled and glanced to his side. He was aiming a handgun right at Raph's head. The red masked ninja was kneeling and a soldier was tying his hands behind the back.

"Tied up for now, they did put up a bit of a fight, but…" the camouflage-pant's wearing turtle trailed off and looked to where the others were tied up and on their knees.

Raph grunted. He should have smelled a trap the moment he saw only four soldiers in the room. The ninjas had all four sprung at them thinking they were in for a short fight, but suddenly soldiers surrounded them, all aiming rifles at them.

There wasn't enough room to maneuver but it didn't stop Raph from trying. He jumped at a soldier but was struck by several lasers. Since they were only set on stun, the turtle was merely immobilized temporarily. Then the Demolisher had arrived and the other ninjas were forced to give up and put down their weapons.

"If you want to free them, feel free to try again. We'll be waiting," Demolisher Raphael said in the shell-cell before crushing it in his hands. Then the turtle holstered his gun.

"Let's keep them in here for now, keep those rifles trained on them. These ninjas are trickier than they appear," he ordered few of the soldiers.

"Bummer dudes." M-Michelangelo hung his head.

"So… anyone mind telling me what went wrong here?" R-wearing Raphael asked once some of the soldiers and the Demolisher left the room.

"You know, maybe charging a room full of soldiers with trained laser rifles wasn't such a bright idea," Mikey remarked.

"Shut up Mikey!" Raph grumbled.

* * *

"Our team has been reduced from seven to three." Leo palmed his face. His counterpart was driving in circles around the neighborhood while they figured out a way into the factory.

"Maybe we should recruit some more help," Don suggested.

"Didn't the cyborg take April and Michelle on a trip?" his brother asked and sighed when he got a positive response.

"Alright, call the Ninja Master." Leo glanced out the window. Then he quickly ducked out of sight when the Turtle-Van passed someone. "Would you mind driving more discreetly?"

"Hm?" his L-wearing counterpart looked at the ninja. "Oh, hey don't worry about being spotted. They'll just think you are one of my brothers anyway."

"Ah right." The basic-green turtle shook his head when remembering that particular detail about this world.

"Hello, you have called the home of Donatello, Luna and Apollo Hamato. Unfortunately we are not at home at the moment, but please leave a message after the beep."

Don sighed when hearing the answering machine message. He tried another number hoping against hope that it would be picked up. The ninja breathed out in relief when he heard the click of someone answering, but blinked when it was the wrong voice.

"General Deputy Clarence McCain, how may I help you?" the voice said.

"Clar? Uh hey, this is Don, you know the teenage counterpart of the Ninja Master," the purple-masked ninja said before inquiring what the human was doing on this number.

"Oh hey there kid. All phone calls to the General Magistrate are being directed to my line for the next week while he is in a conference on Rytonas with the Deputy Magistrate," the deputy explained to the turtle.

"Conference…?" Don blinked.

"Yes, it's a big conference regarding IDA security and law. He took the family with him since he figured they would enjoy the sights in the meantime," Clarence told him.

"Right… uh thanks anyway," the ninja said and hung up shortly later.

"Don?" Leo turned in the seat to look at his brother.

"General Magistrate Raphael, Deputy Magistrate Michelangelo and Ninja Master Donatello are also not at home," the purple-masked ninja explained.

"You are telling me, Donatello, that if we were to meet the assassin in there… we can't reach his brothers?" the blue-masked turtle asked slowly.

"That's what I'm saying," Don told him.

"Well, guess we are on our own then." His brother faced forward again rubbing his forehead tiredly.

"Wait, I have an idea," L-wearing Leonardo said and suddenly took a sharp turn. The only reason the off world turtles didn't get thrown off their seats was because of the seat belts.

"Care to share that idea?" Leo asked gripping the nearby handles tight at the sudden road rage.

"I know some people," his counterpart told him. "Well frogs actually."

* * *

"So what are we going to do with the new prisoners?" The Demolisher asked as he stepped into the lab.

"We'll just keep them detained for now," the ex-emperor said.

"The others will come to rescue them, with back up," the blood-red masked turtle reminded him and leaned on a wall.

 _Ah crud, they captured some of the guys already?_ D-Donatello listened but remained silent. So far his counterpart had been content on working on the computer console.

"I'm very well aware of that, but the soldiers have proven good enough so far haven't they?" the former overlord glanced at the Demolisher. "Also the additional help of Leatherhead and Mad Michelangelo has been essential."

"I'm just suspicious by nature. These ninja boys have proven quite stubborn when it comes to rescuing one of their own. Can't say I blame them though, I would do the same," the camouflage-pants clad reptile grunted.

"Of course, of course." Ex-Emperor Donatello nodded and rose up from the chair and grabbed a clipboard.

"So how is it going here?" Demolisher Raphael eyed the prisoner on the table.

"Slowly, I have never done enough work on this kind of mutagen. I'm still kind of working in the dark here," the lab-coat wearing turtle answered and approached his counterpart. "And he has so far refused to cooperate with information."

"Want me to soften him up for you?" the Demolisher cracked his knuckles.

"Not him, he's too resilient. Bring one of his brothers," the ex-emperor said. His fellow assassin employee grinned predator like.

"I know just the guy." The turtle disappeared out of the lab.

"I can't use the memory extractor; it would take months to file through all the necessary information. My other device won't work on you; your brain has also gotten rather resilient. But you can start talking or the Demolisher starts playing with your brother." Ex-Emperor Donatello glanced down at his prisoner.

"You bloody bastard!" the D-wearing ninja growled.

"Riiight, I can see we are off to a constructive start." The former overlord sighed and started to scribble something on a clipboard.

"Alright, alright, what do you want to know?" D-Donatello surrendered just as the Demolisher walked in pulling R-Raphael behind him.

"Hold on Raphael, seems he is going to cooperate after all," the ex-emperor said.

"Aw," the Demolisher chuckled and threw his counterpart down to the floor. The red-clad ninja was still tied up, both looking a bit frightened and angry.

"Don't tell them anything Donatello!" he shouted.

"Raphael, I can take the punishments. You can't," his D-Wearing brother responded. He remembered all too well the stories of how the Demolisher had treated the R-wearing turtle.

"No way, we can't let the assassin get anything," the R-clad turtle grunted.

"The assassin? Oh, he's not involved in this at all. Couldn't care less about this," the ex-emperor chuckled and then looked at his counterpart. "Start talking."

"And you shut up," the Demolisher stepped on Raphael's plastron and pulled out a handgun. The red-masked ninja narrowed his eyes but remained silent. He was not going to panic, even though the turtle of his nightmares was aiming a weapon at him.

 **End chapter 2**


	3. Chapter 3

**A/N:** Chapter originally written and posted on. 03/05 2008

* * *

 **Chapter 3**

"So where are those frog friends of yours?" Leo asked as Leonardo took another turn. They were now in a completely different part of the city.

"Usually in the swamps in Florida, but I just remembered that Rasputin wanted to check out a science expo here in New York. He's kind of the inventor of the group, you should see his arrows. But anyway, if we are lucky they are already here and trying to sneak into the expo," the L-wearing turtle told him.

"Well at least we have potential back up then. But will it be enough against the turtle soldiers as well," the basic-green ninja wondered, he glanced back at Don.

"Donny, on our road trip in Turtleland, we met up with Yuri and his gang. They did give us contact information, but do you think they would help in this situation?" Leo wondered.

"Since it is against their former overlord?" Donatello rubbed his chin thoughtfully. "It's worth a shot Leo; they might know better how the turtle soldiers work."

"Call them," his brother said and the purple-masked turtle fished up his shell-cell again.

Soon L-Leonardo was driving around a big building, trying to find a secluded spot. Even though this world appeared more tolerant, there was no need to draw too much attention. The van was parked in a secluded alley behind the expo site. The three turtles snuck out but still kept by the van for now.

"Napoleon, are you there?" the L-wearing turtle fished up his turtle-comm.

"Howdy Leonardo, I'm hearing ya loud and clear," a southern accented voice came through the communicator. On the screen appeared what looked like a person in a trench coat and wearing a hat.

"Napoleon, where are you and the rest of the frogs?" the turtle inquired.

"We are inside the expo building with Rasputin; we came just few minutes ago. We were going to call but Rasputin insisted on checking the expo first," Napoleon responded.

"I can understand that, but my brothers and I are having a little trouble and need your help," Leonardo explained. "Can you guys meet me and my friends in the alley behind the building?"

"We'll be right there ol'buddy," Napoleon said and soon hung up. L-Leonardo looked at the other two turtles who nodded. Don was already working on his dimension traveler.

"Don is going to Turtleland to fetch Yuri and his gang, he'll come back here," Leo explained as the purple-masked one disappeared through a portal.

While they waited, four small coat-wearing figures came jumping from a back entrance of the building. They were a bit smaller than L-Leonardo and walked more hunched. Leo raised an eye ridge when seeing those were definitely frogs in trench coat and hats, using sunglasses with fake noses.

 _And that disguise works?_ The turtle blinked but made no comment.

"Howdy fellers," a dark green frog greeted with a wave, the other amphibians greeted in the same way. Underneath the coats, they were wearing brightly colored shirts and shorts.

"Hey guys," L-Leonardo greeted back, then he went to introduce Leo and brief explanation of the whole interdimensional mess.

"Wow, seems like you guys are in deep swamp pile and some," the frog identified as Attila remarked wide-eyed.

"Indeed, we will be glad to help, Leonardo, it will be our pleasure," Napoleon nodded and so did the rest of his friends.

Leo tilted his head as he noted the weapons of the frogs. Rasputin had a quiver of arrows and a bow, Genghis had a double bladed axe with a huge head, Attila had a flail with a big morning star and Napoleon wielded a bullwhip. However, the four amphibians sounded so calm and nice and friendly, the weapons were in stark contrast with them.

Then a portal opened and Don leaped through. After him came seven turtles clad in gray uniforms and six of them wearing helmets, one was holding his under his arms. That one approached Leo and gave an army salute.

"Lieutenant Yuri and his team reporting for duty," Yuri announced.

* * *

"Ok threw him back in with his friends, what is the status?" the Demolisher asked as he reentered there laboratory.

"Well it certainly speeded things up once our subject here finally talked," the ex-emperor said, he was working once more on the computer. His counterpart as usual lay strapped to the table.

"Mad Mike is getting a little restless, I think the previous fight agitated him too much," Raphael grunted and eyed out.

"Well that can't be helped," the former overlord stated and turned back to the table. He pressed a button on a nearby panel.

"OW" D-Donatello shouted when suddenly he felt mild electric shock run over him. However, his counterpart ignored it and immediately turned back to the computer console. He stood hunched over it for a while before glancing back.

"Just as I suspected, my chemical only speeded things up," ex-Emperor Donatello frowned.

"Speeded things up?" Demolisher Raphael arched his brow.

"The instability in the mutagen would have eventually triggered a secondary mutation in my counterpart. My chemical just made the process just quicker," the olive-green turtle explained.

"Wait… if I have unstable mutagen… and my brothers have unstable mutagen." The ninja looked up from the table.

"You and your brothers, if your mutagen isn't stabilized, will eventually mutate into extra-large and nasty mutant turtles. Your previous secondary mutation experience at the ranch proves the nasty part," his counterpart finished for him.

"B-but it can be stabilized right?" the D-clad turtle inquired and felt a small tinge of relief when the ex-emperor nodded, yet it was short lived. He wasn't quite sure if his evil counterpart would actually do that.

"Right so now what?" the Demolisher wondered.

"Now we prepare an extra nasty surprise for my olive-green counterpart, I haven't quite forgiven him yet for helping my cybernetic brother to take away my empire," the ex-emperor growled and grabbed what looked like a taser from the table.

 _Why am I not surprised._ The purple-clad one cringed.

* * *

"I hope the guys will be back quickly," Mikey muttered, he glanced around the room. The soldiers kept a careful watch on them, but still kept a bit away from the four turtles.

"They must be rounding up some backup," Raph said quietly, he looked at Raphael who now lay on his stomach. "You ok?"

"Eh, just been dragged around by the turtle of my nightmares and used as a bargaining chip to get Donatello to spill everything he knew about the mutagen. Other than that, just fine," the R-wearing turtle stated.

"Huh?" the other three turtles looked at him confused.

"Apparently the ex-emperor is messing with mutagen that mutated Michelangelo and me and our brothers," R-Raphael explained.

"Nice," Raph grunted. He looked up when seven turtle soldiers suddenly walked in. _Great, more watchers._

"We are here to relieve you," the first soldier that walked in addressed the guards who had been there before them.

"Huh?" the leader approached the newly arrived. "I haven't heard anything from the Colonel."

"You think he hasn't better things to do than to let you know of the relief when the relief can just tell you anyway it's here to relieve you?" the leader of the new soldiers snapped.

 _Wait a minute, that voice is familiar._ Raph tried to take a better look. He then noticed that the other six soldiers were spreading themselves across the room.

"Well I…" the leader of the room guards started.

"It's not like this is an actual military operation. We are mercenaries as you damn well know," the other soldier growled.

"True but…" the previous one tried to say.

"And you are a bloody stupid one at that." The leader of the new soldiers shook his head. Suddenly his fist shot up and connected hard with the turtle he had been arguing with.

The four ninjas blinked as suddenly the other six jumped the other guards. This was done so swiftly that all nine were on the floor in matter of seconds. The leader removed his helmet to reveal more properly his identity.

"Yuri?" Raph blinked in surprise.

"Hello again, Raphael," Lieutenant Yuri greeted the red-masked ninja. Four turtle soldiers started to work on untying the prisoners.

"Where are Leo and the others?" Mikey asked as he was helped stand up.

"They are going to take care of the alligator and Mad Michelangelo," Yuri told them. "We have to handle the Turtle Soldiers."

"Sounds good to me," Raph growled and spun his returned zai.

"Tie the other soldiers up," the lieutenant then ordered his soldiers. They all immediately complied and soon all nine guards had been stacked up against one wall and gagged.

"Alright men, let's go." Yuri pointed out with a thumb and the seven soldiers plus four ninjas rushed out of the room.

* * *

"Ok let's try this again, you frogs ready?" Leo looked at the four frogs; they looked busy and were gathered around Napoleon.

"You can do it Napoleon," Attila egged on.

"Yes, think about poor Donatello stuck with those villains," Rasputin added in.

"I'm trying fellas, but I just can't get angry enough." Napoleon sighed.

"Angry enough?" Leo and Don blinked and looked at L-Leonardo.

"Uh right, if Napoleon gets angry or upset he kind of mutates to a giant frog," the letter-wearing ninja explained.

"Well we don't have time to wait for that. Yuri and the soldiers have already moved in, we have to take care of Mad Mike and Leatherhead," Leo said and started towards the factory. The other turtles and four frogs followed.

"Hey Leatherhead, we're back!" the basic green ninja called and kicked down the door. He and the turtles jumped in, the frogs carefully peeked through the doorway.

"So ah can see," the large alligator grunted and rose up. Mad Mike snarled and jumped up on a crate. "Come for more eh, and brought da frogs too."

Mad Michelangelo didn't wait for a signal. He charged immediately for the incoming reptiles and amphibians. The Leonardos drew out their swords but Don pulled out his Bo, having picked up a replacement at home when fetching the soldiers. However, they had to duck out of the way as Leatherhead sent cover fire with his laser rifle.

"I'll handle the turtle, fellas," Attila the frog shouted. He managed to jump in and swung his flail, it struck Mad Mike right in the carapace and was stuck there. The mad mutant paid no heed to it and continued to charge, dragging the flail and the amphibian.

"Hey Attila got him," Rasputin cheered.

"Ah I think actually the turtle got Attila," Genghis corrected. The two frogs jumped inside but had to get out of the way from the charging reptile.

"Ahhh! Where is the break on that thing?!" Attila called as he was dragged across the floor.

"Rasputin, quick send a flash arrow," Napoleon called to the arrow-wielding frog.

"Yipe," Genghis ducked behind a crate. A laser fire from Leatherhead reminded them that the alligator was still unaccounted for.

"Ok Attila has Mad Mike distracted." Leo noticed that even though Mad Mike didn't notice the pain he had noticed both Attila and the flail. The mad mutant was now spinning in circles trying to get them off. Genghis tried to sneak over to them to help his friend.

"Just the alligator left," Don grunted and ducked when a laser got uncomfortably close.

"Rasputin, where is that arrow?" Napoleon called.

"Um," the other frog kept searching his quiver. "I think I forgot to pack one in. I got a smoke one though."

"That'll have to do," L-Leonardo was close enough to hear the conversation.

"Alright, nobody try to breathe this in," Rasputin readied the arrow and got ready to fire. A laser hit the bow, smashing it.

"That Leatherhead is really starting to get on my nerves," Napoleon grunted.

"Um Leo," Don blinked and pointed to where the leader of the frogs was. Leo glanced over there and raised an eye-ridge.

"Leatherhead… stop… hurting… my… friends!" Each word got deeper and deeper as the frog suddenly grew larger and larger. Soon he had ripped his clothes, grown seven feet tall and looked pissed off.

"They weren't kidding about the giant frog thing," the purple-masked turtle whispered.

Napoleon growled and ripped off the door from its hinges. Then he used it as a shield to charge towards the laser firing alligator. The two giants crashed into each other and before the others knew it, were engaged in a very heated fistfight. It was hard to tell who was angrier.

"Hey this works." Leo rose up and so did Don and Leonardo.

"We'll keep them busy, you guys get Donatello," Rasputin called. He was fixing his bow. Genghis was trying to pull Attila off Mad Mike, but the other frog refused to let go of his flail. This resulted in a very odd sort of tug-o-war.

"Right, come on guys!" the basic-green ninja said and the three turtles rushed further inside the factory.

* * *

"How many soldiers did they get and from where?" Sergeant Clarence grunted as he, the rest of the soldiers and the four ninjas were behind various crates and barrels. All around laser shots flew around.

"Was just as surprised to see them as you were," Raph grunted, he was the closest to Clarence's place.

"Private Harold and Private Günter get to better cover!" they heard Lieutenant Yuri snap from somewhere behind them.

"Harold and Günter?" the red-masked ninja eyed the soldier.

"Two of our men were still unnamed last time we met. We have since given them names," Clarence responded, before quickly raising his rifle above the barrel and firing few shots.

Suddenly the opposing force stopped firing. Clarence frowned and looked around and so did Raph. They glanced back and saw Yuri slowly peeking from behind a crate. Then suddenly the lieutenant rose up slowly but with his rifle ready. The other soldiers took his cue and the ninjas as well.

"Hello again colonel," Yuri said dryly.

 _Colonel? Oh right._ Raph turned around and saw where Demolisher Raphael had arrived, around him were some twenty soldiers.

"Well, if it isn't First Lieutenant Yuri and this rag-tag team of deserters," the blood-red clad turtle snorted. "I'm impressed; I wasn't actually expecting you to be helping them."

"They asked nicely," Yuri remarked.

"I'm warning you, Demolisher, you bozos let Donatello go now!" Raph growled.

"Or what?" his counterpart eyed the ninja. "Don't forget kid, you are seriously out numbered."

"Hah, I've taken out just about this number all by myself," the red-masked one snorted.

"Um Raph," Mikey tried to interject from his position but was ignored by his brother.

"Oh really have you? Did they usually have laser blasters trained on you in the meantime?" the camouflage-pants clad turtle asked mockingly.

"Your bro looks pissed of," Michelangelo whispered to his counterpart.

"Nah, that's just Raph angry," the non-letter wearing ninja said.

"Oh yeah hide behind the easy to use guns, chickens!" Raph snapped.

"And that's Raph moderately suicidal and angry." The bluish-green turtle frowned a little now.

The Demolisher tilted his head as if he was thinking. Then he waved the soldiers to back off a bit before stepping forward. Suddenly he removed his belt with the explosives and the cartridge strap across his plastron.

"Well if you think you can take me without guns," the blood-red masked one said and threw the equipment to a nearby turtle soldier.

"Right, bring it on Bozo!" Raph snapped and jumped up on top of the crate and then hurled himself towards the Demolisher.

"That is Raph pissed off!" Mikey said palming his face. "And I just had to remember now that our current score against fighting the assassin and his cohorts is currently in their favor."

"Gah!" Don't jinx it dude," M-Michelangelo gasped.

"Yes please, I want to see Raph smear the floor with this guy not the other way around," R-Raphael remarked.

* * *

"Oh nice more soldiers," L-wearing Leonardo sighed as the three turtles ducked out of sight in the large hallway. They could spot few Turtle Soldiers hanging around further away.

"They must be security detail for this area." Leo frowned and looked around. He spotted a door and it seemed to lead to another hallway. The only problem was it was dangerously close to the other reptiles.

"We are going to have to distract them from this door." Don had spotted the same doorway.

"I see four soldiers and they are ready, I think Yuri and his gang have triggered increased security," his brother whispered.

"One is talking on a radio," L-Leonardo noted and frowned. "And they are looking around."

"Uh…" the purple-masked ninja had glanced up and spotted a security camera, it was staring straight at them.

"Oh crud," Leo realized it was too late to disable it. They had been spotted.

"Come out with your hands up!" was suddenly yelled. "We know you're there!"

"Leonardo, you think we can take them?" Leo glanced at his counterpart who smiled and nodded.

"Hey, what about me?" Don asked frowning.

"You are going through the door, Don, if this leads to your counterpart, you are the best to deal with him," the basic-green turtle told his brother. "Leonardo and I will cover you."

"Alright then." The olive-green one nodded.

Suddenly Leo sprung up throwing surikens straight at the soldiers. Then he and L-Leonardo charged for them. Some of the stars hit weapons, leaving three soldiers unarmed. The fourth started to fire and almost hit Leo.

Don quickly used the opportunity to follow and then duck through the doorway. Quickly he ran after the hallway towards an open entrance. The turtle glanced back for a moment but could hear that his brother and Leonardo were still fighting; they were not going to follow him for a while.

The ninja burst through the second door only to end up in a room with some computer equipment and a table. On it was his D-Wearing counterpart strapped. Behind it stood ex-Emperor Donatello, holding a taser like device.

"Let him go emperor." Don frowned and went for his Bo staff.

"Ah! Ah! Ah!" The former overlord narrowed his eyes and moved the device closer to Donatello's neck.

"Don't be too hasty on the staff, Donatello, or our counterpart here will receive a very nasty mutating experience," he then warned.

"What do you want, in fact what is the assassin doing here now!" Don demanded and reluctantly let go of his staff, he hadn't unbelted it.

"My employer is not involved in this. This is a private expedition on my part. He lent me the muscle power of the Demolisher and Michelangelo though, but the assassin is as far as I know at home with his sons," his evil counterpart responded.

"As for what I am doing here, I already did tell your counterpart that. I wanted to see why he reacted so badly to my soldier boosters," he then answered.

"I could have told you that. That's because his mutagen is unstable," Don retorted, he and the D-wearing turtle had in fact done plenty of experiments regarding that particular event.

"I like it more when I discover it on my own, besides not every time I can play with such large sample of mutagen." The former overlord smiled now. His ninja counterpart then noticed the can of mutagen on the roller counter.

"Well the experiment is over, let Donatello go," Don said and folded his arms seeing that he was currently not in position to grab his weapon.

"I have to admit I also did this because I knew you and your brothers would come to the rescue, especially you," the ex-emperor snorted.

"What do you mean?" the purple-masked one asked, then glanced at his silent D-wearing counterpart. However, he had been gagged.

"It's because of your meddling in my lab that the cyborg got free and I was overthrown," his evil counterpart snapped.

"What? The Assassin, for your information, sent me there in the first place. I was happily minding my own business before he did that," Don protested. "He messed with your transpad, he cooked up the entire accident that caused us to switch. I was just trying to get back home. I wasn't planning on toppling any empire at all."

"You didn't have to mess with my computer equipment at all. You only needed to report yourself to a soldier and he would have taken you to the cyborg who could have verified your story anyway." The former overlord pointed out.

"Yes, I was very keen on being found out to be intruding in the emperor's private laboratory," Don snorted dryly. "Like it or not, this was the assassin's whole fault. The fact you are still working for him is mind-boggling. He even tried to blow up your own daughter, or have you forgotten the factory?"

"Michelle would have been safely transported away. I rigged the cradle trap myself, she would have been unharmed," the ex-emperor growled.

"Ok this is just a wild guess. But are you holding this stupid unfounded grudge against me because you are just too afraid to try to go up against the assassin?" Don asked.

Much to his surprise the former overlord started to laugh. D-Donatello glanced up with raised eye-ridge, just as confused as his non-letter wearing counterpart. That had obviously not quite been the reaction they had expected.

"No I work for him because I get good equipment to play with. Honestly, Turtotopia was established by accident, I never really wanted to be an emperor. But hey it had its perks while it lasted." The former-overlord shrugged. "I'm mostly mad at you for messing with my equipment and causing Tella to be destroyed. You know how hard it is to compile a decent AI?"

"Uh," Don was not quite ready to answer that one.

"And Donatello, you should know that I can be just as dangerous to mess with as the assassin is." Ex-Emperor Donatello suddenly smiled very strangely. "I'm just not the assassin type dangerous."

"I'm the mad scientist type," he then clarified and operated the taser device. Then the turtle put it right up against D-Donatello's neck, sending electric current through his body.

 **End chapter 3**


	4. Chapter 4

**A/N:** Chapter originally written and posted on. 26/05 2008

* * *

 **Chapter 4**

 _Whoa._ Raph just barely managed to duck as the heavy fist almost crashed into his skull. The ninja narrowed his eyes and used his position to quickly make a dragon-tail kick.

However, the Demolisher saw it and jumped, as he was landing the heavy turtle prepared to punch down. The younger one quickly rolled himself away. His counterpart landed, punching the floor instead and leaving a dent.

 _Ookay, forgot how strong he is._ Raph frowned. After his slight growth spurt few weeks ago, the ninja was now almost just as tall as the other turtle. However, there was no hiding it that the Demolisher was stronger with his bulk.

Thus the red-masked turtle found himself in the situation where he was actually the more agile one. Something he didn't always find himself, being usually the powerhouse of the team. He quickly jumped hoping to kick his counterpart in the face.

It connected and the Demolisher staggered back, but only used the back of his hand to wipe the spot. Then he charged with a snarl, the turtle managed to grab Raph and send both of them crashing into crates. There they kicked and punched each other for a while.

"You know," R-wearing Raphael remarked where he and the others were watching the fight. "I can't decide which one is angrier."

"Eh who cares, just kick back and enjoy the show," Mikey chuckled, leaning now on wall.

Raph managed kick the Demolisher off, sending the blood-red masked reptile flying. He crashed into few turtle soldiers who weren't fast enough to move out of the way. The others nearby helped their colonel to stand up.

"Had enough?" the ninja asked as he back-flipped up.

"Barely started, kid!" Demolisher Raphael grinned. He cracked his knuckles and ran for his counterpart again.

"Have those two fought each other before?" M-Michelangelo wondered.

"Yeah… two times I think, back when we were rescuing you and your bros from the ranch," Mikey told him.

"Well I'm just glad to see someone actually being ABLE to fight him," R-Raphael grunted.

"Will you stay down!" Raph growled as he kicked the Demolisher back, but his counterpart only took few steps backwards before charging yet again.

"I got a better idea, why don't you stay down," the older reptile growled and managed to land a heavy punch on the ninja. Raph was thrown several feet back and crashed down in front of R-Raphael.

"He's not simple to take down is he?" the letter-wearing turtle remarked.

"Grrrrr!" his counterpart growled and rose up. With a loud growl he charged right back for the Demolisher.

* * *

"Donatello!" Don shouted when the ex-emperor used the taser on their counterpart, he started towards them but stopped in shock.

The D-clad turtle screamed in pain at first but then it turned deeper and sounded more like a roar. The ex-emperor backed away as the ninja suddenly began growing. The expanding arms and legs blew up the straps and the table crumbled under the sudden weight of the reptile.

Donatello had on just few seconds grown to almost nine feet stature, shell and plastron had become far thicker and heavier. The skin was no longer green but strangely brown-yellowish. The head was much more lizard like and the muzzle had a row of sharp teeth and a forked tongue. He sported claws on finger and toes now that looked deadly sharp, insanity shone in his eyes.

At that moment Leo and Leonardo had disposed of the soldiers and came running inside. They both stopped short at seeing the rising monstrosity facing Don. However, it was clear to them who it was, the now damaged D-Belt and the purple gear still hung on the behemoth.

 _Woah… Déjà vu._ Leo blinked.

"D-Donatello?" Leonardo whispered, but then the monster charged the olive-green ninja.

"DON!" Leo threw himself up against his brother to throw him out of the way. In the process he collided himself with D-Donatello.

"Leo," Don turned where he had landed and saw his counterpart pick the now unconscious blue-masked turtle.

"Donatello, let him go!" Leonardo threw himself up against his brother. The huge turtle slammed his clawed hand against him. The L-clad turtle was thrown off.

 _Wait the emperor._ Don looked around but unsurprisingly the former overlord had booked.

"Okay no time to think about evil overlords." Don realized that his extra-mutated counterpart was turning his attention back to him. Leo still hung limp in the huge left hand.

"We have to get him to drop Leo and… subdue him somehow!" L-Leonardo was rising up rubbing his sore head.

"Any ideas?" Don asked and slowly rose up, keeping an eye on his growling counterpart who was approaching.

 _I don't think even Napoleon can take on Donatello right now._ the letter wearing turtle cringed.

D-Donatello charged again and Don was forced to jump out of the way. He hated to do run, but there was nothing visible in the lab that could be used. They needed something else and it was not available here. The purple-masked one thus managed to grab for L-Leonardo's hand and drag him out.

"W-wait what are you doing?" the blue-clad one asked.

"We need something else to subdue your brother. However, I need to use the dimension traveler to go get it. I rather not have him charging at me when I open a portal. It would stop him more permanently than I care for," Don explained as they ran after the corridor. Right behind them came the extra-mutated turtle roaring, breaking the walls and the ceiling as he chased them.

"But what about Leo?" Leonardo asked.

"He hasn't harmed him yet and I think I know who can keep it that way while I go and get the equipment," Don said as he dragged his brother's counterpart back to the factory room.

Napoleon was still battling Leatherhead but Rasputin, Genghis and Attila had fled up to a high platform. Below it, Mad Mike paced around, growling and snarling eyeing the three terrified frogs. They had all lost their weapons in the process of battling the mad mutant.

"Now to get Mad Mike pissed off at your brother." Don pushed L-Leonardo away so now only his huge counterpart was chasing him.

The purple-clad ninja headed right for where Mad Mike paced, knowing that D-Donatello wouldn't stop for anything. The turtle quickly jumped right over the angry mutant. Mad Mike whirled around and almost started to chase Don. Then the behemoth like a steamroller walked right over him.

Mad Mike snarled and charged for the usually D-wearing turtle. He jumped and latched to the big right leg biting hard and clawing. The behemoth roared in pain and stopped, he began shaking the leg wildly to get the smaller turtle off.

That was the distraction Don needed, quickly the purple-clad one whipped up his dimension traveler and was out through a portal. The three frogs on the platform and L-Leonardo stared blinking at what had happened.

"Uh where did the other turtle go?" Attila asked.

"I think I know…" The turtle looked around, everybody were ignoring him. Napoleon and Leatherhead hadn't even noticed their arrival, throwing each other around. D-Donatello was trying still to kick Mad Mike off his leg.

* * *

Yuri eyed the other soldiers, he was pretty sure they would resume firing once the fight was over. The turtle glanced back to where the two counterparts engaged each other. Neither looked ready to stop anytime soon.

"You alright sir?" Williams asked. He was next to the lieutenant.

"I will be, the moment we have somehow dealt with all those enemy soldiers," Yuri muttered.

"You know I didn't realize the Demolisher was this good." Mikey scratched his head.

"Maybe the Assassin dude is training him?" his M-wearing counterpart suggested.

Out of a side door, ex-Emperor Donatello came running. The lab-coat clad reptile halted and almost hit a turtle soldier in the process. He raised an eye-ridge at the duel between the Raphaels, then looked towards where the others were.

"Uh oh, Mr Sinister is here." Mikey cringed when seeing the former overlord. The M-clad one gulped too. Even though they knew he didn't possess much fighting capabilities, the ex-emperor still could freak them out.

"Raphael, we don't have time for this. I had to send Donatello against the others as a distraction. Let's collect Mad Michelangelo and get out of here!" olive-green turtle shouted.

"What does he mean by that?" R-Raphael frowned.

"Alright kid, we'll call it a draw," the Demolisher grunted and landed a kick on Raph that threw him a bit back. "Fire!"

The twenty soldiers aimed their rifles and immediately began firing. The red-masked ninja barely managed to duck for cover and the others hid behind their previous hiding places. Yuri and his gang tried to return the favor few times but they were out gunned.

 _Hm?_ Yuri glanced up when the laser shower suddenly stopped. He just missed the last of the enemy soldiers disappear through the same doorway that the ex-emperor had come from.

"They're booking!" the R-wearing turtle blinked. Raph growled and jumped up.

"We'll see about that," the non-letter wearing ninja snorted and immediately headed after them. The others followed soon after.

* * *

Leo groaned softly as he came too. The turtle slowly opened his eyes only to realize he was swinging madly. Firmly around his waist was a large clawed hand. The turtle shouted out when the hand swung with him towards the floor but then was lifted again.

"What is going on?" the blue-masked turtle cried out. Then noticed who was holding him, extra-large D-Donatello was still trying to get Mad Mike off. In the process his prisoner was swung around.

 _Shell he's strong._ Leo tried to pry himself loose but he was held firmly.

"Leo!" L-Leonardo appeared. He was trying to determine how he could help.

"Leonardo…. Remind me to apologize to your brother once we reduce his size!" Leo called back and drew out one katana; both swords had somehow managed to stay in his scabbards. Then he tried to stab the fingers holding him.

"Wait Leo, his skin is…" the letter wearing turtle saw what his counterpart was up to, but was too late with the warning.

 _Ooooh crud._ The basic-green ninja frowned in worry when his sword broke in two. _But wait, somehow Mad Michelangelo is harming him._

Trying to glance down when the hand was less moving. He did indeed notice that Mad Mike's claws and teeth had effect. Either the claws were made out of different kind of metal, or the legs had weaker skin.

"Here goes nothing," Leo muttered and drew out his remaining sword, the hand swung again and came close to the left knee. The turtle cut with the sword, only intending to give what might be considered a slight paper-cut.

D-Donatello roared in pain and released his hold on the ninja. Leo landed nimbly on his feet and immediately got out of the way. The large turtle didn't get a chance to go after him, Mad Mike was still latched to his right leg.

"For some reason… not that I'm complaining… his skin is weaker on the legs," Leo wheezed, feeling slightly crushed after the iron grip.

"Uh Don went back to your world I think." L-Leonardo ran over to his friend. "To get something to stop Donatello."

"To stop him…" The basic-green ninja raised an eye-ridge. "Must be the…"

He didn't get further. Suddenly twenty turtle soldiers plus Demolisher Raphael and ex-Emperor Donatello came charging into the room. The soldiers immediately fired towards the ninjas to get them out of the way.

"More soldiers!" Leo growled and managed to duck and then drag Leonardo to cover.

"We're booking, Leatherhead, ya coming with us?" the Demolisher called and whistled loudly to get Mad Mike's attention. The mad mutant jumped off D-Donatello's leg and raced towards the blood-red masked turtle.

"Ah be right dere!" the alligator growled and managed to land a hard enough punch on Napoleon to send the frog back. Then he charged towards the soldiers.

"They are getting away!" Leonardo cried and rose up. His extra-mutated brother roared and started to chase the fleeing bad guys.

It was then a black portal opened and out of it, Don jumped through. He was dressed up in Leo's monster hunter gear. Quickly the purple-masked turtle aimed for his behemoth counterpart and started to fire the small blue cylinders. They contained the sedatives strong enough to stop him. D-Donatello was hit several times on the legs and the effects started to show soon after. The turtle slowed down before crashing to the floor unconscious.

"Good work Donny!" Leo came running and so did Leonardo.

"Yeah… I'm glad I remembered when you told how you stopped me when I mutated." Don glanced at his brother and then to the unconscious giant.

"Wow… I've never been so angry in my life." Napoleon came staggering, having shrunk back to his normal size. The frog looked a bit disoriented. Then Raph, Mike, Michelangelo, Raphael and the other turtle soldiers came running in. They stopped short when seeing the scene.

"Where are the scumbags?" Raph growled and looked around.

"They escaped," Leo told him, his brother cursed and kicked some scraps near him.

"Hey look!" Don pointed at his counterpart. D-Donatello was shrinking back and didn't stop until he was back to normal.

"It must have only been temporary," Leo commented as the turtles gathered around the unconscious reptile.

"How did ya fellas get up there?" Napoleon spotted where the other three frogs were.

"Uh you know, frogs see danger, they jump." Attila shrugged, he, Rasputin and Gengish grinned innocently.

"I've got antidote back in the lair for this sedative. You guys take him there, I'm going back to that lab first, just in case," Don said after checking his counterpart over.

"I'll come with you," L-Leonardo offered.

"My team will secure the perimeter, make sure everybody have in fact fled," Yuri announced and saluted the ninjas. The turtle soldiers then disappeared out of the factory.

"Well it was fun, but we better get going, the expo will be soon over," Rasputin commented as he jumped back down with the other frogs.

"Thanks for your help frogs, we couldn't have done it without you," L-Leonardo thanked his amphibian friends.

Soon only Don and he were left in the factory. The others were instructed to go back with D-Donatello. The two ninjas traced their steps back to the lab where the brainy turtle of the letter-wearing team had been kept captive.

"Looks like the computer equipment survived your brother's wrath," Don said and cracked his knuckles before starting to work on the consoles. "Let's see here…"

"I think it was because you had him chase us out rather soon afterwards," L-Leonardo suggested.

"Hmm…" Don merely hummed as he was already busy reading what was on the computer.

"Find anything yet?" the letter-wearing ninja wondered and try to see on the screen, but he couldn't make much out of what stood there.

"Oooh, just the way to stabilize the mutagen in Donatello and the rest of you," the purple-masked one said and glanced at Leonardo with a grin.

The blue-clad turtle blinked, he was of course aware of it now that he and his brothers were at risk, the instability in the mutagen having been explained to them all. However, so far neither Donatellos, not even the Ninja Master had managed to find a way to stabilize it.

"Wait a minute… don't you think this is a little bit convenient?" the L-wearing turtle frowned.

Don stopped working on the computer and looked up. The turtle frowned heavily as he considered this. Glancing around, he spotted a canister with glowing substance. He picked it up and then eyed his brother's counterpart.

"This is the mutagen that mutated you guys right?" he asked, L-Leonardo nodded.

Suddenly out of the console shot out robotic arms. They grabbed a firm hold on Don who yelped and dropped the canister. The L-wearing turtle jumped and managed to grab it before it hit the ground. Looking up he blinked when seeing the purple-masked turtle struggling to break free from the computer, but he was held firmly up against it.

"Ahahahahaha!" A mad laughter started to echo through a speaker on the computer.

"How do you like my nasty surprise, Donatello! You thought I was going to kill you by using your own counterpart? No, he was only an incentive for you to come back here to see if I had been working on something with him. Something that might help stabilize the mutation in him," it was the voice of the ex-emperor.

"Yes this whole setup was just to lure you into this trap. I knew you would smell a rat if I did this in your world so I set it up in this one. Knowing the turtles here would call for you and your brothers for help. After all, you honorable ninjas help your friends don't you? Now I better not bore you with a pointless monologue, enjoy the last ten seconds of existence!"

"Ten seconds?" L-Leonardo blinked.

"There is a bomb in the computer! I can hear it tick!" Don cried and tried even more desperately to break free.

"No!" The blue-clad turtle put the canister on the floor and drew up his swords. Swiftly he cut the robotic arms holding Don. Then he quickly pulled the olive green turtle away from the computer. The purple-masked turtle grabbed the canister and the two ninjas fled the lab. They barely managed to throw themselves out before the room exploded.

"That… was too close for comfort," the olive-green turtle whispered where he lay on the floor in the hallway. He glanced back cringing. "That… bastard was really going to kill me."

"So this whole thing was just to get rid of you?" L-Leonardo sat up frowning.

"It… it appears so," the purple-masked one whispered, bit shaken after the near death experience.

"But… why does he hold such a powerful grudge against you? You just happened to be in the way… it was the assassin who engineered everything." The blue-clad one scratched his head.

"I-I… I have a thought…" The purple-clad one frowned now. "The cyborg mentioned it to me once… back during that time when I switched. How much I reminded him of how the ex-emperor used to be."

"Right… you are a more carbon copy of him than my Donatello." Leonardo nodded.

"Exactly and well… I've been in constant contact with the cyborg. He looks at us, my brothers and me and Splinter as his family now." Don looked at the blue-clad ninja. "He's jealous."

"Jealous?" L-Leonardo blinked.

"Yes… I'm living the life he could have been living. This isn't about the empire or that stupid computer of his. For him… I stole his brother away, his daughter and his wife. He's jealous of me. He has to live as a fugitive under the good graces of the assassin." Slowly the purple-masked turtle rose up.

"You really think that is the reason?" the letter-wearing turtle wondered.

"It fits. He well aware that it was the assassin is responsible for the downfall of his empire. However, he never cared that much about it. It was just bonus side effect of what he was originally doing. He cherishes his intellect more but the most startling part of all, he actually cares a whole lot more about his brothers' than he himself will ever admit," Don explained.

"Remember few weeks ago, when were in those underground caverns of the clone cyborg? The emperor was contacting Raphael to use him to translate the computers. He was genuinely startled and concerned when hearing how low on power the cyborg was, even shouted at him to turn off the link they were using in real alarm," the purple-clad one continued, weighting the canister of mutagen in his hand.

"Wow." Leonardo glanced back at the room that was now on fire, but it hadn't spread out much.

"Let's get out of here, my Leatherhead and I can use this mutagen to find a way to stabilize your mutagen," Don muttered and went for this dimension traveler.

 **End chapter 4**


	5. Epilogue

**A/N:** Chapter originally written and posted on. 26/05 2008

* * *

 **Epilogue**

 **2k3 TMNT-World**

"There that should do it, let's take some samples just to make sure," Don said to the four letter wearing turtles who stood in front of him.

Each had a metal cap with wires connected to it, as well as everyone had IV tube connected to the arm. With his world's Leatherhead help, the olive green turtle started to disconnect the gear. It had soon all been removed from the letter buckle ninjas. Shortly later, they were either rubbing their arms or cracking sore joints in their necks.

"You really think it worked?" D-Donatello asked with a heavy frown, he, his counterpart and Leatherhead had been working on the stabilization for three days straight by now.

"Well only one way to find out," the olive green turtle told him and started to gather blood samples from all four ninjas.

"Man I hope it does," L-Leonardo muttered. M-Michelangelo nodded in agreement.

"Eh you guys let me know how it goes." R-Raphael shrugged and started to walk away from the lab and towards the entertainment area. Raph and Casey were there watching a movie.

Leatherhead, Don and Donatello went to work on the blood samples. Leonardo and Michelangelo watched and waited almost in dread. It took another full hour before the crocodile looked up to give the verdict.

"Hm, I do believe the mutagen is stabilized," he announced. The three dark-green turtles and the olive green one sighed in relief. Leonardo and Michelangelo then walked away to give R-Raphael the good news.

"Yes!" the D-wearing turtle grinned and gave Don a high three. Then he bent over the microscope to take a look himself. His non-letter wearing counterpart watched for a moment but then unnoticed reached for his dimension traveler.

"Great work Do… uh Don?" D-Donatello looked up but the olive-green turtle had disappeared from the lab. Leatherhead looked around just as surprised.

"He was here a moment ago," the large reptile blinked.

* * *

 **Turtleland**

April opened the door and was mildly surprised to see the person standing in the doorway. Michelle came running and almost flew through the entrance.

"Unca Donny!" She giggled and hugged the olive-green ninja.

"Hey Michelle," the turtle chuckled now holding the little girl. "Hello April."

"Come on in, Don, what brings you here?" the woman asked curiously and let the reptile inside.

"Mostly to meet Raphael," Donatello answered.

"He went to the marker; you know where that is don't you?" April explained to him, recalling that the cyborg had shown the ninjas where the marker was.

"Yes I do," the turtle nodded. Michelle was already trying to tell him what she had been doing just a moment ago.

"Wish I could stay and listen 'Ellie but I need to talk with your daddy first. But I will come and play once I'm finished," the turtle told the little girl before sliding her back to the ground. He didn't escape quite so easily just yet, she had to give him a farewell hug on the leg first.

The ninja headed back out and took into the direction of the marker. It was a bit of a walk, but he was used to long distances. The purple-masked one was soon approaching the hill that had the marker Cyborg Raphael put up in memory of his brothers. He spotted immediately where the mechanical turtle was.

"Well I'll be damned," the large reptile chuckled when spotting Don climbing up the hill.

"Hello Raphael," the ninja addressed the mechanical one.

"Hey Don, what brings you to this corner of the multiverse?" The cyborg rose up and faced the younger turtle.

Don didn't answer right away; he walked past the mechanical turtle and stared at the marker. Three names were carved on it, despite that one was still alive. Cyborg Raphael watched the ninja without a comment. He figured that something was on the ninja's mind but had to be said on his own pace.

"I… met your brother again few days ago." Donatello finally turned to look at the cyborg. Then he told him what happened. Without a word, the mechanical reptile put one hand gently on the ninja's shoulder.

"If Leonardo was still alive… do you think he would have done the same as you? Adopted us… me like you did." The purple-masked one looked at the marker again.

"Would he? He already did back in the private laboratory. Even at one time when you were sleeping, he was singing you a song he used to sing for Donny-boy. Yes, he would have considered all of you as his brothers. That's just how Leo was. Always ready to accept people with open arms. He would have become just as bad mother hen and your Master Splinter already is," the cyborg chuckled at the last bit, already aware how fiercely protective the old rat was of the four ninjas.

"I am honored… to call you my brother Raphael, you've not just been a friend to me and my family," Don whispered, still staring at the marker. "You have helped us so much when we've had to deal with the assassin…"

"I've lost three brothers, Don. I know how it is to lose someone. I'm not losing someone I care about again, not if I can help it," the cyborg said silently.

"Raphael… in all seriousness, when you thought I was the emperor… were you really going to kill me?" the olive-green turtle looked at the cyborg.

"No Don I wasn't. My whole intention was to scare you. Then I would have forced you to stand down as the emperor," he answered. "In all honesty, Don. I was maybe built as a killing machine, but I do not kill willingly unless in self-defense of others or me. The only other times I killed was when my brother was controlling me."

"Yeah," Don nodded. "Let's go back. I promised 'Ellie to play with her."

"Now that is a promise no one can back out of," the cyborg chuckled and the two turned away from the marker and started to walk down the hill.

* * *

 **Assassin's world**

Ex-Emperor Donatello folded his arms and sat with a frown in the chair. He tried to ignore the mad laugher coming from the couch. The assassin sat there and sounded more as if he had been taking in too much laughing gas.

His employees had returned three days ago, safe for the otherworld Leatherhead who had been paid for his job and left. The Demolisher gave him a communicator so they could stay in touch. The alligator had expressed interest in working for them again if they wanted, having thought the previous job to be very fun and well paid.

The next three days had then gone into making sure nothing could be traced to the Assassin. He had merely funded this thing but was not involved at all. Not even Leatherhead's communicator would do that, it would call the Demolisher and not the black clad turtle.

The former-overlord had though planted a security camera in the room where Don had gotten trapped. The footage was sent directly to a computer in this world, so it didn't pose any security risk. The two turtles had just recently had time to view that footage.

"Oh… my… that was hil….hilarious." Assassin Leonardo finally stopped laughing and started to dry away the tears. He sat up, looking at the ex-emperor grinning wide.

"T-That had got to be the most stupid and yet the most hilarious thing I've… ever seen before." The black-masked turtle giggled and broke into another laughter fit.

"Should have set the timer for five seconds," the olive-green turtle grumbled.

"Ten seconds, five seconds? You shouldn't have had a timer at all!" The assassin stopped laughing again shaking his head.

"You… you had this near perfect trap, you managed to trap the guy only for him to escape almost immediately afterwards." the black-clad turtle tried desperately not to start laughing again.

"Ok let's review this. You manage to lure him in, you manage to get him to go and check what you were up to. Then the computer traps him, so far so good. But Donatello, the bloody monologue and the timer is where you failed so miserably." Leonardo leaned back in the couch and regarded the ex-emperor.

"First of all, little Donny was wise enough to take someone with him to check the computer. Both the monologue and the timer gave Pretty Boy plenty of time to free him. If you really wanted successful result, the trap should have exploded the moment the robot arms pulled Donny's face into the console."

"I'll remember that next time," the ex-emperor growled. The assassin started snickering again.

"If you do, make sure to film it again so we can see you fail again," the black-masked turtle laughed, rose up from the couch and left the living room. Leaving the former overlord grumbling in his seat.

 **The end**

 **A/N:** You can almost call this story my homage to the 80's cartoon and I got to admit, as short as this story is, I absolutely loved writing it, especially 80's Toon Leatherhead. The story was only created though to address a plot point I made in in Shattered Shells regarding the unstable mutagen in the 80's Turtles and have that fixed, it also answered what Emperor Donatello was up to at the end of the Nightmare Codes and gave people idea what happened to Yuri and his gang.


End file.
